It is common in the transfer of low temperature liquids through pipelines, for example, in the transport of products such as propane (-56.degree. F.), butane (+28.degree. F.), ethylene (-160.degree. F.), or LNG (-260.degree. F.), all of which are characterized by low temperatures, to employ a single insulated pipeline for the transfer of the low temperature liquid and a physically separate vapor return line in which the vapor resulting from boiloff from and displacement in the receiving vessel is returned to the storage tank or sphere. A typical conventional low temperature liquid pipeline system which would require separate vapor return facilities is found in U.S. Pat. No. 3,693,665. Reference also may be made to API 2510 and NFPA 59A for further details with respect to conventional systems presently contemplated and used. Such conventional arrangements present the problems of accommodating or restraining the large thermal movements associated with cooldown of the liquid pipeline, adequately insulating the liquid pipeline excessive heat leak into the cold liquid, and satisfying space requirements for two separate pipelines rather than only one in existing facilities where available space may be limited.